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Oil coming out

Annmarre

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I've already replaced the turbo on my 6.5 and stopped all oil leaks except I'm still having a problem with losing oil from where the upper intake manifold and the turbo come together. There is oil that's blown out onto the plastic and rubber. All the bolts are tight as well. Does anyone have a thought of why this is happening? I'm not getting any back up where the oil stick goes or around the oil cap. Thank you in advance. We're also still trying to get it out of limp mode from where the TPS was replaced. That was adjusted already. 93 GMC K3500 4L80E Tranny auto 4x4
 
You need to check and see how much blow-by you have. With the engine idling remove the oil fill cap and watch for air movement , it will look alot like smoke. None indicates a healthy engine. The more you have the worse shape the rings are in. Having said that these engines will run an amazingly long time with substantial blow-by. I have yet to see a 6.5 that has a clean oil free intake.
 
How many miles and condition of the truck.

AK beat me to it while I was typing

As in excessive oil or its wettish? Its normal for the intake of a 6.5 to be wettish. After years my rubber hose turbo to intake manifold is sorta oil soaked. The turbo pulls oil vapor out of the engine to re-combust it. The CDR is supposed to limit the vacuum the turbo draws. An excessively dirty or restrictive air filter will also increase the vacuum of turbo and increase wetness of intake.
 
Install a catch can in line and eliminate the cdr is best. If emission laws in your area require the cdr then you can still use it.

Not one turbo manufacturer thinks it’s a good idea to let oil hit the blades while turning 10,000 rpm- only GM bean counters. The intake valves get buildup and that has its own host of issues. You waste oil and therefore money burning the oil. The annoying part of the leak is low on the list of why to do this.
 
How many miles and condition of the truck.

AK beat me to it while I was typing

As in excessive oil or its wettish? Its normal for the intake of a 6.5 to be wettish. After years my rubber hose turbo to intake manifold is sorta oil soaked. The turbo pulls oil vapor out of the engine to re-combust it. The CDR is supposed to limit the vacuum the turbo draws. An excessively dirty or restrictive air filter will also increase the vacuum of turbo and increase wetness of intake.
I can let you know tomorrow how many miles are on it because I can't remember exactly but it's over 100 thousand. My truck is in good shape being that it was a city work truck. Still rides as smooth as ever when the tranny isn't in limp mode lol. It's wettish like what you're describing. I've had diesels but they've been cars. I love having a diesel truck!
 
Thank you, I will replace it.

Don't throw parts at it without being sure. You need to check for blow-by. Take the oil fill cap off and start the engine. Anything huffing or steaming out of the oil fill cap. If so how bad?

What was the reason for turbo failure and replacement? As the turbo was replaced it would be a good idea to inspect the boot between it and the intake for proper install or damage. Are the clamps tight?

The TPS is a cake walk to set.
Adjust the hot engine RPM to 650.
Back probe the ground and the signal wire. The 3rd unused wire will be 5v with the ignition on.
Disconnect the cold start solenoid green wire.
Set the TPS signal to 0.5V to 0.6V. Closer to .5V without going under the better.
Snap the throttle open and closed a few times to make sure it doesn't "bounce" below 0.5V.

Inspect the wiring back to the firewall for damage. Inspect the wiring for the "speed/RPM" sensors on the transmission, there are two, esp. where the wires go into the harness for insulation "falling off". Common problem. Look for oil leaking out of the main transmission electrical connector.

Have you pulled codes? Limp = A Code in ECM.

What codes have you seen or do you have?

Look up the paperclip method if needed to read the codes out.
 
Don't throw parts at it without being sure. You need to check for blow-by. Take the oil fill cap off and start the engine. Anything huffing or steaming out of the oil fill cap. If so how bad?

What was the reason for turbo failure and replacement? As the turbo was replaced it would be a good idea to inspect the boot between it and the intake for proper install or damage. Are the clamps tight?

The TPS is a cake walk to set.
Adjust the hot engine RPM to 650.
Back probe the ground and the signal wire. The 3rd unused wire will be 5v with the ignition on.
Disconnect the cold start solenoid green wire.
Set the TPS signal to 0.5V to 0.6V. Closer to .5V without going under the better.
Snap the throttle open and closed a few times to make sure it doesn't "bounce" below 0.5V.

Inspect the wiring back to the firewall for damage. Inspect the wiring for the "speed/RPM" sensors on the transmission, there are two, esp. where the wires go into the harness for insulation "falling off". Common problem. Look for oil leaking out of the main transmission electrical connector.

Have you pulled codes? Limp = A Code in ECM.

What codes have you seen or do you have?

Look up the paperclip method if needed to read the codes out.
I'm sorry, I've been really busy getting ready for my daughter's wedding. As soon as I can get over to my truck I will check everything for you.
 
I'm sorry, I've been really busy getting ready for my daughter's wedding. As soon as I can get over to my truck I will check everything for you.
Thank you. I haven't gotten to my truck at all yet. It just hit me, what if it wasn't adjusted right. I may need to have my insurance tow it home because nothing is getting done to it over where it's sitting.
 
Most up town mechanics do not have an inkling of a clue when it comes to doing anything on the 6.5. Best to follow advised procedures Yourself, save some money in the process and know what to do should the same conditions ever reoccur.
I think it was around 2000 when the CHEVY/GMC dealers started phasing out 6.5td techs in Southeast Florida so I had to use an AM General truck store for service.
 
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